img[src$="null.gif"] {  
    background: transparent url(../images/BugImageBundle.png) no-repeat scroll 0px 0px; 
    width: 16px; height: 16px; 
    margin: 0; padding: 0;
}
img.BugSprite { background-position: 0px 0px; }
img.BugAddSprite { background-position: -16px 0px; }
img.BugDeleteSprite { background-position: -32px 0px; }
img.BugEditSprite { background-position: -48px 0px; }
img.BugErrorSprite { background-position: -64px 0px; }
img.BugGoSprite { background-position: -80px 0px; }
img.BugLinkSprite { background-position: -96px 0px; }